86 Corolla 4AC rwd thermostat location

Does anybody know the location of the thermostat on a 1986 Corolla SR5, rwd, 4AC engine? My manual says the thermostat housing is where the top radiator hose connects to the engine but this housing contains 2 sensors and lots of vaccum hoses and looks too skinny to house a thermostat. The bottom radiator hose connection at the water pump looks more like a thermostat housing and looks like it can be removed from the water pump but I have never seen a thermostat at this location. Any help will be appreciated.



The Autozone repair guide also shows the thermostat located under the outlet at the upper radiator hose:


Maybe you should remove it and take a peek…

It’s been a while since I changed one, but yes, it’s not in the usual location. It is where the lower hose connects. Only thing you have to watch is to put the new thermostat back in the same way the original came out. HTH.

Autozone is wrong, and the replacement thermostat they sell won’t work, been there, done that. It is where the lower hose connects and you will need two o rings as well. When you remove this housing, there is a bypass pipe that has to be removed at least at one end, that is where the o ring is needed.

A thermostat from the dealer isn’t much more that the one from Autozone.

You have a very popular car with the drifters, though they prefer the 4AGE engine over the 4AC

This is a reverse flow cooling system. That’s why the thermostat is located down low.

Just curious Keith, is the t-stat in the same lower hose location on the 2002 and up Corollas?

I don’t think the 4AC was made past 88 or 89. If it has a 4AFE engine, it might be in the same place, but I’m not sure. They have the same shortblock, same family anyway, the heads are interchangeable.